Figure 1.

1-Methyl-dl-tryptophan (1MT) treatment reduces fungicidal activity, NO, kynurenine (Kyn), and indoleamine-2,3 dioxygenase (IDO) production by pulmonary dendritic cells (DCs) of Paracoccidiodes Brasiliensis-infected mice. Pulmonary DCs were obtained from 1MT treated or untreated A/J and B10.A mice at 96 h (A,C,E) and 2 weeks (B,D,F) after infection with 1 × 10⁶ yeasts and cultivated for 24 h at 37°C in 5% CO₂. The cells were centrifuged, resuspended in 100 µL of culture medium and assayed for the presence of viable yeasts by a CFU assay. Supernatants from DCs cultures were used to determine the levels of nitrite and Kyn. In the same experimental conditions, DCs of A/J and B10.A mice were mixed with TRizol reagent for RNA extraction. IDO mRNA was measured using TaqMan real-time PCR assay. IDO was also characterized by immunoblotting. DCs were lysed, supernatants supplemented with a protease inhibitor and protein concentration determined by a BCA assay. After electrophoresis in polyacrylamide gel, proteins were transferred to nitrocellulose membranes and stained with anti-IDO antisera. Densitometry of bands was performed using ImageQuant TL 8.1 software. NO production was measured by Griess reagent, and Kyn were evaluated using Ehrlich’s reagent. The data represent the mean ± SEM of three independent experiments where the asterisk (*) represents a statistically significant difference between treatments (*p < 0.05, **p < 0.01, and ***p < 0.001) and the hashtag (#) represents the difference between the strains (^#p < 0.05, ^##p < 0.01, and ^###p < 0.001).